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First time accepted submitter THE_WELL_HUNG_OYSTER writes "I have 10-15 old hard drives I want to trash, some IDE and some SATA. Even if I still had IDE hardware, I don't want to wait several weeks to run DBAN on all of them. I could use a degausser, but they are prohibitively expensive. I could send them to a data destruction firm, but can they be trusted? What's the fastest, cheapest DIY solution?"

An angle grinder with any metal-cutting bit will slice clean through the platters and circuit boards, making a pretty shower of sparks. It's much more satisfying than just using a drill, and at least as effective as swinging a big hammer on them.
BTW, remember that destroying hard drives could easily be construed as "willful destruction of evidence" if you're later accused of anything (terrorism, copyright violation, or other heinous crimes). So, whatever method you choose, it might be advisable to destroy them out of the public eye...

You can make a kiln for almost nothing. Bury the drives in a barrel of sawdust, with large holes at the bottom of the barrel, and light it from the bottom. You can fire clay with a primitive kiln like that, it should be hot enough to melt the drives.

Here in Greece we have some volcanos that are easily accessible by the public and in fact some schools go there regularly. Last time I heard children went to either to the island of Nisyros or Santorini. There are plenty of holes to the ground that lava is visible. You can drop your hard drive there. Don't breath over the holes, I heard they smell terribly of brimstone. Don't fall inside. PS: Santorini is a great island to go to the summer, so perhaps you can combine those two activities.

Much ado about nothing. Remove the circuit boards. There'll be nigh chance in hell anyone will find a matching board for that model ***and that batch*** in order to get at the data. Toss the drives afterwards. And degaussers are rarely reliable.

I had a friend who's drive was killed in a lightning strike. A friend of theirs swapped out the control board for another one. It physically fit, but released its magic smoke after just a few seconds. So, I inherited someone elses botched repair. Of course, I was 1,000 miles away, so it's not like I just stopped by to say "hi", and took a look at it.:)

I did some digging, and found a guy who would send you the appropriate replacement board for something like $40. It would help to have the original board, but he figured out which board was correct for this drive, and it took a whopping 5 minutes to install. Most of that was finding the screws and screw driver.:)

The only way to assure a drive is completely unrecoverable is physical destruction. Simple as that.

Personally, I dismantle them for the magnets, and pull the platters out. If they're ceramic you can shatter them, if they're aluminum you can deface them, bend them, use the magnets to corrupt them, cut them in half with a hacksaw/bandsaw/whatever, be creative.

A shock wave passing through the material causes enough local heating (and a lowering due to pressure) to pass the curie point (there's papers about that happening in iron powder composites) - but a shock wave that big is most likely going to come from the sort of impact that would shatter the glass platters anyway.It's glass in those drives. A big drop onto a hard surface is probably all you need instead of ovens and explosives.

A shock wave passing through the material causes enough local heating (and a lowering due to pressure) to pass the curie point (there's papers about that happening in iron powder composites) - but a shock wave that big is most likely going to come from the sort of impact that would shatter the glass platters anyway.It's glass in those drives. A big drop onto a hard surface is probably all you need instead of ovens and explosives.

For practicality, I like the kind of HDD-destroying "shock wave" produced by putting a number of 3/4-inch holes clean through the drive in the platter area with a drill press.

Several good whacks with a 10-pound sledgehammer to top it off, and whoever wants to recover anything useable/useful off of that particular drive had better have some mad skills, low expectations, and a long time to spend doing it!

Besides, if there are people willing to try recovering data from a drive of yours after such measures, you

The "wrong" moderation is not required because some are glass as you would have noticed if you've read about them or even better pulled some apart (and broken a platter or two - fracture surface looks like glass and is even transparent in the uncoated bits). They make good mirrors apart from the hole in the middle.A "not always right" mod may apply because not all of them are glass, but I never said they were but I suppose somebody attempting to read too much between the lines could assume I meant that with "It's glass in those drives". Maybe I should have written "a hell of a lot of drives have glass in them" but somebody that's never looked inside or read anything about their manufacture or never found some other way to get the merest fucking clue would probably still "correct" me before finding that even Wikipedia (http://en.wikipedia.org/wiki/Hard_disk_platter) is a good enough source!What I don't know however is if it's haematite or magnetite on the surface of those platters since I've never stuck one under a microscope - anybody here know? It's obviously an oxide since fingerprints on the polished surface don't corrode and fingerprints on polished steel (and ferrite) corrode quickly enough that you can almost see it happening.

I actually use a hammer most of the time. Take the drive, put it at a 45 angle leaning against a parking curb, then star wacking it with a small sledge. Creasing the platters is really all it takes to render them unreadable.

If you're really bored, or really paranoid, go buy yourself a 20ton shop press and smash them with that. They're around $300 for a cheap one that will work well enough.

Well, for those of us living in the civilian world, C4 is hard to get our hands on.

Thermite, on the other hand, can be made rather easily from things around the house. A file or grinder, a bit of the appropriate metals, and an ignition source. Be sure that your "Member of the Overkill Club" card is up to date, and you're all set. 5 pounds of thermite vs 1 hard drive sounds just about right. Well, right through the drive, and the table, and the concrete below.:)

Actually, thermite may be the better choice anyways, unless you want to notify everyone for miles that you're using C4.:) It has lots of hot, and not much bang. Well, especially compared to C4.

And remember kids, don't try this at home. It's a really really (really) good way to burn down your house, get the police called by a neighbor, and/or be charged with arson and building explosives. Some law enforcement folks don't look upon such things as lightly as they used to.

Ever tried to cut aluminum sheet with an oxy torch? If you don't contain the heat, you'll often get exactly nowhere. Stuff conducts heat way too fast to cut in some circumstances. I'd say make a little oven out of ceramic -- bricks will probably do. It will melt at strawberry red, but it won't cut.

If you don't want to get into pyrotechnics but you have firearms: A.308 will do the trick.

This. My boss at my old IT job used to go out to a firing range with one of the server guys on their lunch break and shoot old drives with a bunch of different guns. It makes a pretty awesome looking exit wound.

I do the same thing at work. We have a wet saw for cutting welding samples and it cleanly slices through all kinds of metals without much of a problem. I put the drive on the table and run the blade into the platters about half way. It slices through the drive like a hot knife through butter. That disk will never be read again.

Another way is to run them over with a forklift as they weigh twice as heavy as their lifting capacity. So a 6000 pound capacity forklift weighs in at around 12000 pounds meaning each tire has a crushing force of about 3000 pounds. Just don't do that on asphalt as your going to leave an imprint of the drive in it or possibly mush the drive into the pavement. I know not everyone has a fork lift but its one way to do it. I got that tip from a UPS driver who informed me that is how he destroys his old disks at work. I tried it and it seems to work very well. You just need a very heavy fork lift.

Burning a drive doesn't guarantee it will destroy it unless you bring its temperature well over 1000F. And I believe the case of the drive is made from zinc which melts at 787F making it a liquid metal mess. Also, its circuit board will burn causing quite a stink so its one of the least clean methods of destroying a drive.

And lastly the good ol' hammer works great. Just wear eye protection and your all set for some destructive fun. Just make sure you smash the platters and not just the circuit board. Use a cold chisel or punch to better focus the blow to the platters. Its simple, fast and just about everyone has a hammer lying around. Just do it on a hard surface like pavement or concrete. A kitchen table or counter top will deaden the blow and your almost guaranteed to damage them in the process.

They turn it on, the drives get launched by the magnetic field and hit someone in the head, causing permanent brain damage. They then use the drive serial numbers to track them to you and sue you in the gutter.

Magnetic drill bits don't drill any better than non-magnetic drill bits. What's your point? You still need to drill the platters into small bits before you can be relatively certain no useful information can be retrieved.

I don't know if they have reduced the MRI magnet strength over the years but when I got one about 10 years ago they told me the strength was 3 Webers. Looking up a quick translate table, 1 Weber = 1 Tesla, so either the old ones were 10x more powerful than the ones today, or you're an order of magnitude off.

But yeah, letting one go within 20 feet of an MRI would suck it in so quick it might shoot out the other side, or maybe the field would be strong enough to just hold it once it sucked it in.

For more cool scenes of devastation check out the image where an MRI sucked in a FORKLIFT! No shit, one of those large pallet jacks you use to drive pallets around factories, must weigh 100-150 lbs and it had NO PROBLEM sucking that into the maw of it's magnet, destroying it thoroughly, of course. Image is here: http://www.howstuffworks.com/question698.htm [howstuffworks.com] - check it out, if you ever had ANY doubt about the power and strength of an MRI magnet.

so you could just walk in (hold drives very tightly), and keep them in the machine for a while.

Not the best idea as the drives would be ripped out of your hand and fly towards the machine at a high enough velocity to kill anyone in the way. Oh and you would probably destroy the MRI in the process.

There is a very good reason why you don't take metal anywhere near an MRI machine.

Which acid? HF to attack the glass (if you are insane enough to fool about with HF if you don't have to) or something else to attack the oxide coating?I've seen hot citric acid used on an industrial scale to clean magnetite out of boiler tubes but dilute nitric didn't seem to do anything to the magnetite on samples taken out of boiiler tubes for analysis. Would phosphoric acid work?

nail gunhammer, bigger may be betterscrewdriver, there are cool, powerful magnets inside and the aluminum chassis is recyclable for cashsteel wool on the platter once taken apart (not really important by that time)Firearms, play safe

I did it today to one. Unscrew them, take the plates, throw them in different recycling bins/garbage cans/whatever. If you're concerned about someone snooping in your garbage, drop one off at a different gas station every morning. Plus you get some neat looking polished Al/Ni discs out of it if you don't feel like throwing them away...12 year old drive's guts were shinier than a bathroom mirror today

If you're looking for fast production-line destruction, take a three pound hammer and punch. A punch driven through the aluminum plate covering the platter section, midway between the center spindle and the edge of the drive, down to the bottom of the case through the platters, will effectively destroy the disks. It will cheaply render the data unreadable to anyone who doesn't want to invest ten thousand dollars investigating the remains of the disks. You can crank through many disks per hour. A 3/8" bit in an electric drill would be similarly effective, and less labor intensive than a hammer, but slower.

Leaving the aluminum plate covering on the drive has the added advantage of containing the shards if the disk platters are made of glass. Even so, I'd wear leather gloves and use eye protection if I were physically destroying them this way.

But with 15 drives, it's just not that big of a job. Why make a big mess? Disassemble them. It takes about 10 minutes per drive, and it's both educational and fun. You can probably do it watching TV on the couch.

A miniature Torx driver set (T6-T9, available from Sears), a flat bladed screwdriver, a #2 Philips screwdriver, and a pocket knife is all I need to take most drives apart down to their components. Recover the voice coil driver magnets, they're always useful. Remove the circuit boards and recycle them as they were probably soldered with lead. Remove the platters from the spindles. To truly be rid of the data, you'll have to basically destroy the platters in a very hot fire. Heating them past their Curie point will completely destroy the data, leaving them totally unrecoverable; but that may require heat as high as 1500 degrees F. You won't get that on a stovetop.

Be careful with some of the components if you are letting children have them or play with them.Some drive platters are glass instead of aluminum and it is very difficult to know the difference from handling them. My daughter dropped one on the floor and it shattered into very dangerous shards. I was shocked as I believed they were all aluminum. I think most IBM/Hitachi Deskstar drives are glass but there could be others.She really loves the rare earth magnets but learned real quick that the can pinch very e

^----- this. When all that's left is a pile of melted aluminum there is nothing to recover. Even with a hole in the drive or a shredded drive there's still intact pieces, if you really want to do it right you have to melt it down to just aluminum.

Open it up, pull the plates out, and run through each one via a shredder, using the slot for CD-ROM if your shredder has one, otherwise the normal slot for paper is fine. Just make sure you don't put it more than one at a time, and be prepare to endure the noise it generates.

Yes, their has been. I used to work for a group that did this. Our clients were BIG corperations and guys in cheep black suits. It really comes down to how much time and money you are willing to put into it, but 60% recovery was possible 3 years ago. Your not going to get that using the hardware on the drive (yes, the platters have to come off), but it is possible to get with the right tools and equipment.

There was, but that was in the times that the air was clean and sex was dirty. A large capacity drive was 20MB and comprised of 4 platters in a 5.25" enclosure, double the size of a CD-ROM drive.

The original question stated no connecting the drives up to a computer was possible, since the owner didn't own anything that still had the required connectors/controllers to do so. Zeroing out isn't an option within the constraints given.

There is a lot of talk about "with specialised equipment, wiping with zeroes doesn't wipe" but AFAICT, when actually pressed nobody ever follows that up with "and I know of this data recovery company that can do it". My own research suggests that there was once an academic paper which suggested reading a drive with an electron microscope as being hypothetically possible but didn't actually go ahead and do it; Steve Gibson has posited somethin

With specialized equipment drives can be easily recovered when wiped by zeros. With even more sophisticated methods drives that have been written over several times can be recovered layer by layer.

Easily?!?! Layer by layer? Do you have personal experience recovering overwritten data in this fashion? If so, please let me know, my company would hire you in a heartbeat and you could name your price. This concept has been trashed over and over again on slashdot, and nothing has changed since the last time.

Think of the signal for a single bit on a platter like a digital Jackson Pollock painting using only two colors. One color represents a 1, the other color is a 0. Each write is a new splatter that gives the picture a new dominant color, but there are still some pixels left over from the previous splatters around the edges. Once the color of a pixel is set, it is set until you change it and you have no idea if the same color pixel next to it was written at the same time or not. You can just see that the overall color of the entire image is one or the other.

Now let's say, just for the sake of this discussion, that you were actually able to read these mythical "layers", or more appropriately, all the drops of the various splatters. Because this is a magnetic signal and not a physical layer of paint, you have no idea when any given pixel was written compared to the one next to it. There is no concept of a layer because the signals aren't stacked on top of each other, they are all next to each other. Now let's say that you have somehow managed to design and build the most sensitive magnetic read head ever conceived so that it is able to read the signal of every single molecule in the space that this bit occupies. That's great. Now you've determined that there were a bunch of 1's and 0's. Which order were they written in? Did that 1 from over to the left come before or after that 0 that you read from the lower right?

Assuming you got that figured out, now you need to get the next 7 bits just to make a byte. Did you get all 8 bits from the same write put together? Or did you screw one up because you got the ordering of your "layers" a little mixed up?

Now that you've got an entire byte reconstructed, you need to do the same with the other 511 bytes for the sector. Did you get all 4,096 bits for the sector correct for your "layer" of data? I'm a little skeptical...

Now go get the rest of your file, because it probably isn't all contained within a single 512 byte sector, and it may very well be written to different regions of the drive if it wasn't all written as a contiguous allocation. Depending on the file system and the size of the file, it's could be guaranteed that it is not contiguous - ext3 will be non-contiguous if it is larger than 6K.

Now that you have every bit recovered for a single file, did you get every bit correct? You're most likely in trouble if you screw up even a single bit and try to open it with the native application. LZ-based compression used for the file? It's almost sure to be busted as soon as you hit that bad bit and you won't be able to decompress anything beyond it. Different files have different tolerances, but unless you plan to look at everything with a hex editor, you're probably going to have a lot of trouble. Even something like a Word document (*.doc, not the *.docx) isn't going to be as easy as you think because the file does its own allocations of 64 bytes at a time within the file. If you did any edits, or have anything other than just plain text that is all the same font style, your text is no longer contiguous. If that Word document is using the new format (*.docx), then you out of luck because it is using a variant of LZ compression.

Oh, the file was a picture? No, still not always going to help you. Certain graphics file formats, like JPEG, do tolerate some corruption of the data (depending on where the corruption shows up), but some are just as fragile as a compressed data file.

Now repeat this for every file until you find files that are actually valuable to you. The amount of effort needed to reconstruct anything that has been overwritten far exceeds the value of whatever data it was.

I seem to remember seeing a hydraulic press/punch being used by someone - - put a nice one inch hole in the hard drive and that was that but it wouldn't take long to take them out and just smash the platters with a sledgehammer...or using the sledgehammer itself on the hd may be fun too

What - we just had the "omg how do I save my pictures/videos for my great-great-great-grandchildren!?!?" 3-monthly Slashdot story, so now the "aaaargh! I can't let some schmuck discover all the home made porn and paste it all over the interwebs!!!" was overdue?

Seriously, people... HDD tech hasn't changed enough to make the same answers from 5 years ago any different now.

I can't stand "security" people in business in general with this impulsive urge to physically destroy hard drives because of the data they stored.Go do some googling, a simple ONE PASS of 0's on the disk WILL make the data absoloutely, without question unrecoverable, anyone who tells you otherwise is in to voodoo and black magic or trying to make some profit.

A huge amount of these "security professionals" insist on trashing perfectly good hardware for no apparent reason, it's a complete was of good resources.The amount of perfectly good disks I've seen killed is astounding and not always old clunkers either, some relatively decent sized, high performing disks to boot.

DBAN doesn't take forever either, hook them up to a spare PC and fire it off, change the disks every couple of hours, infact if I recall DBAN supports multiple drives at the same time.Sure if you have a 40gb IDE or something, just drill a hole in it - but if you're trashing anything over 160gb you're starting to ruin perfectly good hardware, for the sake of being pedantic and frankly stupid - stop and just don't do it.This goes for anyone else suggesting the same thing, go and do some reading before believing any of this "must be 12pass write" rubbish to a disk.FWIW A good 0 write to a disk doesn't normally take more than a few hours.

Physical destruction is appropriate for used drives because they're really bad resources. Spinning disk drives are machines that wear out over time. They get a few thousand hours on them, and then they die.

I've measured the actual MTTF of drives that had published specs promising 300,000 hours MTTF. Of a population of 24 drives, I had 30% mortality within 60,000 hours (with somewhere near 25,000 being the mean.) That means we saw quite a bit less than the 300,000 promised hours. And these were the all-

I was about to post this myself, but DBAN will do the trick. There's practically no way anyone will recover anything but a few random strings of plain text out of that, and that's only if they have the analog tools in a forensics lab. Even the chance of reconstructing a usable credit card account out of that is in the same probability range as guesswork.

But I will say that your estimate of 200GB is pretty low for what's worth re-using unless you're broke. Any drive that's been in use for 3-5 years is well p

What I find funny is the contradiction. When you want to make data unrecoverable, you have to do some serious abuse. Drilling a hole might not be enough! But when a hard drive begins to fail, somehow that same data is so delicate that any mistake, or no mistake, will lose it all, no recovery possible.

old hard drives that are too small to be worth someone's time reusing (really who needs a 20 gig hard drive)

He said some were SATA; I really doubt any SATA drives would be that small.
It's just machismo: "My data is so evil and important that the NSA would spend a million dollars to recover it so I have to reduce the disc to constituent atoms".

Bollocks. Just write zeroes over it and you are safe in the real world. CSI and 24 notwithstanding.

âoeAny modern drive will most likely be a hopeless task, what with ultra-high densities and use of perpendicular recording I donâ(TM)t see how MFM would even get a usable image, and then the use of EPRML will mean that even if you could magically transfer some sort of image into a file, the ability to decode that to recover the original data would be quite challenging.â)(Article itself) http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html [auckland.ac.nz]

If you're destroying drives on your own, go for it. But in any kind of business, even if you don't have some old motherboard with an IDE connector, it's worth spending the $20 on an adapter or card to just DBAN those crappy old drives.

Why? Solely to prevent someone from injuring themselves while destroying old hard drives with a drill, which is bad in itself. It's worse when they bill the company for the ER visit because a spark gets in their eye. It gets even worse when they go on perfectly collectible wor

There are really some voodoo and black magic that can recover data if you erase disk that way. Last time my colleague has to pay ~US$600 on his own accord to recover data on a harddisk he accidentally overwrote with a ghost image. We didn't call for rocket scientists's help, just paid a specialist and the data was back.

Sounds more like that the data wasn't overwritten, the specialist just located the data on the disk and assembled it together. That's a whole lot different thing than trying to recover data that was overwritten and it sure as hell would cost a four-figure number, not ~$600.

Also, you would like to be aware of the fault-tolerant design of modern harddisk that might replicate data in hidden storage, which might be up to 15% of the published space. So, erase 7 times with patterns, degauss, or even physical destroy is really necessary for erasing sensitive data.

Not needed. A single ATA "secure erase" command is enough as that command also clears out remapped bad sectors and other areas only the drive itself can access.

Very powerful magnets in the drives. Open them up, take out the magnets, and throw away the drives. If you are really paranoid, pop the discs out. But definitely salvage the magnets. They come in handy.

Oh sweet jesus, my sincere apologies for the travesty above. Proof reading is obviously a skill I need to work on.

I did this just this week, but with floppy disks. I keep three neodymium magnets stuck to the heating pipe on the other side of the room, with a piece of cardboard folded around them to form a handle. I tried one disk with readable data before and after: Data readable before exposure, "The disk is not formatted" afterwards. I waved the magnet over the disk two or three times, and it was all gon

I always just take the platters out, run a magnet over them and hang them on my wall. I play with the platters fairly often as well so there's not a whole lot of chance for any data recovery. Plus they look cool!

One pass with zeroes or random data over the whole drive is sufficient, unless you expect that a large government agency is going to open up the hard drives and spend millions of dollars to attempt to recover the data (and even they might be unable to get at the overwritten data. See http://www.nber.org/sys-admin/overwritten-data-guttman.html [nber.org]).

With dd if=/dev/zero of=/dev/sdb you can wipe all the hard drives in a weekend.

How likely is it that someone is ever even going to try and get the data off the disks? Obviously it's not national security data or you wouldn't be asking here. Put it another way, how much is your data worth to others? Would someone want to invest $10, $100, $1000, or $1000000 of effort in trying to recover it?

For something different - open the lid of the drive, put some sand in there, close the lid, give it a vigorous shake, then power it up. It should be destroyed in no time.

I am going to be boring and tell you what I learned from the founder of a data recovery company.

1) One single pass of zeros is enough. urandom if you want to be paranoid.2) If you want, or need (auditing, etc), to physically destroy the drives: Bend the platters. As soon as the platters are bent, you can not spin them for data extraction, any more. Keeping in mind the distance between head and platters, even the slightest bend becomes irreparable. And as soon as you can't spin them, you are looking at scanning the whole platter without any fancy off-the-shelf controller logic.

According to him, those are the only two cases when they tell the customer over the phone that they don't even have to bother sending the disks in.

...the best way to guarantee that a drive will immediately become permanently unreadable and unrecoverable is to put the only copy of some really important data on to it, and let nature do the rest.
(What? Doesn't nature hate you too?)

Unless these disks are inoperative (and you say using DBAN is an option so I guess they aren't), don't physically destroy them! One overwrite with any data - ones, zeroes or random - is enough to make the data unrecoverable on a hard drive made in roughly the last 20 years, according to US NIST (just be sure to use a tool that overwrites bad sectors as well). You can do two if you're super-paranoid. If you want to do more than that, seek professional help - psychiatric help, not IT help.

Just open it up with a torx wrench, and sand the platters by hand with some 60 grit paper until they're not shiny. The magnetic dipoles only goes a few tens of nanometers deep on the surface of the platter.

It depends who you're trying to hide your data from. When I bin a hard drive, I'm only worried about two-bit scam artists going through my trash and finding some meet for identity theft, maybe manage to skim a credit card number, They'll be more than thwarted by bashing the thing with a hammer a couple of times until the plates rattle and the connector is mashed out of shape.

It might not protect me from the full might of the world's intelligence services- but they're not exactly a main concern of mine.

When I worked as a Data Security Tech we formatted them with 1's and 0's 7 times before crushing them with a drill press. NO ONE could recover that data.

You crushed them with a drill press? Here's a tip: the switch on the drill press makes the pointed thing spin, and you can turn the handle to make the pointed thing put holes in the hard drives. It's much less work than crushing them.

It doesn't work as well as you'd think - believe me, I've tried. What tends to happen is the thermite melts a small hole through the drive, and all drains to the bottom, where it burns a hole in the container and continues further down away from the drive. Even if you use a suitable container (for example, a bucket full of sand), it's difficult to get the whole drive to melt, and there's no way to know if the surviving platters got anywhere near their Curie point. Plus it's a pain in the ass to get the thermite to ignite, and the resulting thick black smoke may very well have your neighbors calling the fire department.

In the end, it's much simpler and less frustrating to simply smash the thing to pieces with a sledge hammer. Thermite for its own sake is fun and (kinda) educational - it's just not a good tool for this job. If you're really paranoid, do a single pass of zeros (or ones, if you prefer) before breaking out the hammer, but it probably isn't necessary. Unless the FBI's hunting you, no one's gonna put in the effort to recover data off a smashed platter.

Actually, there are a whole bunch of industries that have to destroy hard drives appropriately. Anything with names, address, DOB, SSN, CC#, etc... If an old drive that you let out of your custody is found, and even a small bit of data is recovered, that comes down on you like a ton of bricks. Well, a ton of lawsuits.

You are correct though, we have our procedures specifically outlined. There's no question, check with the boss. There should be a formal written policy on it somewhere. If not, you aren't handling sensitive information, and/or you aren't in compliance.

You know what's funny? I have drives to destroy. 1,500 of them. There was sensitive data on them, so they have to be physically destroyed. If we were to go that route, it'd take... well, it'd probably cost more in drill bits than it's worth.:)

We found a local place that'll run drives through their shredder. No piece bigger than 1/4". They get to keep the scrap metal, but we have to transport the drives. Easy enough. If you look around enough, you're bound to find someone with such a facility.

Speaking from experience, it is usually more than enough to overwrite the whole disk with random data. Even a single pass is usually enough to thwart any attempt at reconstruction.

But, for the truly paranoid, you have to bypass or trick the controller to also overwrite the remapped bad sectors. That's not trivial a task, or, more precisely, it depends heavily on the controller's firmware and drive model.